Backing up a storage groups data to another device to be held off site in DPM 2007

Our enviroment is pretty simply, two offices in the states, one DC/file server in the UK and one DC/file server in Ireland that are all backed up twice daily over a WAN link using MS DPM 2007. The DPM works great but keeps everything locally.

Basically what I would like to do is take a copy of all the data that is on the DPM for the two overseas sites and put it on a external disk once a month. Doing an ntbackup over the WAN would take forever.

Is this possible? If I haven't been clear enough please just let me know.

Look into Quantum's DXI line.. It's a disk-based virtual tape library (LTO4 emulation) that uses data de-duplication to reduce the amount of data stored, and it can automatically replicate with other DXI's..